Verification code generator for Node.js

!Version

> Simple library to generate verification codes without dependencies for Node.js.

This library utilizes in-built Node.js module crypto to effective random numeric sequences generation, but also you can implement your own function to generate random sequences, using simple contract: function (charCount: number ) => string

$3

From version 1.1.4 support of legacy nodejs was dropped. Now minimal version of nodejs is 14.

If you need this library for node 12 - please downgrade to version 1.1.2!

Usage

If digital codes is only what you need - just use shortcut getDigitalCode

``js
const { getDigitalCode } = require('node-verification-code')
const smsVerificationCodeBuffer = getDigitalCode(4) // Will produce Buffer contains 4 random digits

// sendSms(phone, smsVerificationCodeBuffer.toString())
`

Own alphabet

Library is built on two entites:

* generator - function which generates Buffer with random content any length. It utilises sequence-function to produce random sequences
sequence-function - function which provides sequence of random elements (up to 10 symbols*)

> Although sequence size is limited to 10 symbols, it doesn't mean you cannot generate longer codes. Generator will call sequence-function multiple times to get code with desired length.

So, to create own code generator you will need to create your own sequence-function. To do so you can simply use sequenceFromAlphabet shortcut as follows:

`js
const { sequenceFromAlphabet, createGenerator } = require('node-verification-code')

// create sequence function
const emojiSequence = sequenceFromAlphabet(['🐶', '🐱', '🐭', '🐹', '🐰'])

// create generator from sequence function
const getEmojiCode = createGenerator(emojiSequence)

getEmojiCode(4).toString() // -> for example: 🐹🐭🐹🐰
`

Also, you can create your own sequence function by hand, just implement (number) => string contract and pass it to createGenerator:

`js
const { createGenerator } = require('node-verification-code')

/*
!!! only shown as example, don't do this in real code - crypto module produces better results

Sequence-function contract implementation:
(number) => string
*/
const mathRandomSequence = (charCount) => '0'.repeat(charCount).replaceAll('0', () => Math.floor(Math.random() * 10))

// Create code generator from sequence
const makeMyOwnVerificationCode = createGenerator(mathRandomSequence)

// Generate code
makeMyOwnVerificationCode(4).toString() // -> for example: '2108'
`

Install

`sh
npm install node-verification-code
`

Run tests

`sh
npm run test
``

Author

👤 Tominov Sergey

* Website: https://ikfi.ru
* Github: @ikenfin

Show your support

Give a ⭐️ if this project helped you!

---

_This README was generated with ❤️ by readme-md-generator_